Her blouse

You decide to make her take off her blouse.

"Mom. I command you to take off your blouse" You say nervously but also kind of excited.

"Yes Master" Lily agrees. "Wait, what?" She says. "Why would I take off my blouse?" She asks as she uses both of her hands grasp the sides of her blouse and begin to slowly lift it up. "John what's happening? Why am I taking it off? Why am I doing what you are telling me to do? What did you do to me?" She asks angrily.

You watch as your mom slowly lifts her loose purple blouse over her flat, slim stomach and then over her boobs, revealing a red lacy bra which is just see-through enough to be able to get a rough idea of what her boobs might look like. Unfortunately, the intricate pattern cleverly covers her nipples so that you cannot see everything.

"It's simple mom" You explain while she strips. "I have made you obedient. You will do anything I say, no matter what it is" you continue to explain before your mom drops the blouse on the floor.

Having just taken her blouse off, Lily quickly covers her bra with her arms. "Wait really?" She says in shock. "Y-you're disgusting. A pervert!" She argues, despite secretly being turned on by it. "Let me put my blouse back on right now!" She pleads.

With her blouse now off. She still has plenty of clothes still on.